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  • AMC 8: [year] AMC 8 Problem #, Ex: 2013 AMC 8 Problem 1
  • AMC 10: [year] AMC 10A Problem # OR [year] AMC 10B Problem #, Ex: 2015 AMC 10A Problem 16
  • AMC 12: [year] AMC 12A Problem # OR [year] AMC 12B Problem #, Ex: 2021 AMC 12B Problem 25
  • AIME: [year] AIME I Problem # OR [year] AIME II Problem #, Ex: 2013 AIME I Problem 8
  • USAJMO/USAMO: [year] USAJMO/USAMO Problem #, Ex: 2023 USAJMO Problem 1
  • Codeforces: Codeforces [contest id (e.g. 101)][problem id (e.g. A, B, C)]: [Codeforces problem name], Ex: Codeforces 1336F: Journey
  • AtCoder: AtCoder [contest id (e.g. ABC314, ARC164, ZONE2021)]: [problem id (A, B, C)]. [Problem name], Ex: AtCoder ZONE2021: E. Sneaking
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  • USACO: [year] [contest month (e.g. January, US Open)], [division (e.g. Gold)]: [Problem name], Ex: USACO 2023 US Open Contest, Bronze: Rotate and Shift

ID Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)
6950 Codeforces 1527D: MEX Tree
6949 Codeforces 1527C: Sequence Pair Weight
6948 Codeforces 1527B2: Palindrome Game (hard version)
6947 Codeforces 1527B1: Palindrome Game (easy version)
6946 Codeforces 1527A: And Then There Were K
6945 Codeforces 1526F: Median Queries
6944 Codeforces 1526E: Oolimry and Suffix Array
6943 Codeforces 1526D: Kill Anton
6942 Codeforces 1526C2: Potions (Hard Version)
6941 Codeforces 1526C1: Potions (Easy Version)
6940 Codeforces 1526B: I Hate 1111
6939 Codeforces 1526A: Mean Inequality
6938 Codeforces 1525F: Goblins And Gnomes
6937 Codeforces 1525E: Assimilation IV
6936 Codeforces 1525D: Armchairs
6935 Codeforces 1525C: Robot Collisions
6934 Codeforces 1525B: Permutation Sort
6933 Codeforces 1525A: Potion-making
6932 Codeforces 1523H: Hopping Around the Array
6931 Codeforces 1523G: Try Booking
6930 Codeforces 1523F: Favorite Game
6929 Codeforces 1523E: Crypto Lights
6928 Codeforces 1523D: Love-Hate
6927 Codeforces 1523C: Compression and Expansion
6926 Codeforces 1523B: Lord of the Values
6925 Codeforces 1523A: Game of Life
6924 Codeforces 1521E: Nastia and a Beautiful Matrix
6923 Codeforces 1521D: Nastia Plays with a Tree
6922 Codeforces 1521C: Nastia and a Hidden Permutation
6921 Codeforces 1521B: Nastia and a Good Array
6920 Codeforces 1521A: Nastia and Nearly Good Numbers
6919 Codeforces 1520G: To Go Or Not To Go?
6918 Codeforces 1520F2: Guess the K-th Zero (Hard version)
6917 Codeforces 1520F1: Guess the K-th Zero (Easy version)
6916 Codeforces 1520E: Arranging The Sheep
6915 Codeforces 1520D: Same Differences
6914 Codeforces 1520C: Not Adjacent Matrix
6913 Codeforces 1520B: Ordinary Numbers
6912 Codeforces 1520A: Do Not Be Distracted!
6911 Codeforces 1519F: Chests and Keys
6910 Codeforces 1519E: Off by One
6909 Codeforces 1519D: Maximum Sum of Products
6908 Codeforces 1519C: Berland Regional
6907 Codeforces 1519B: The Cake Is a Lie
6906 Codeforces 1519A: Red and Blue Beans
6905 Codeforces 1517H: Fly Around the World
6904 Codeforces 1517G: Starry Night Camping
6903 Codeforces 1517F: Reunion
6902 Codeforces 1517E: Group Photo
6901 Codeforces 1517D: Explorer Space
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